The largemouth bass (Micropterus salmoides) were subjected to three distinct experimental feeding regimes: a control diet, a low-protein diet containing lysophospholipid (LP-Ly), and a low-lipid diet incorporating lysophospholipid (LL-Ly). One gram per kilogram of lysophospholipids was incorporated into the low-protein (LP-Ly) and low-lipid (LL-Ly) groups, respectively. The experimental results, collected after a 64-day feeding period, demonstrated no statistically significant distinctions in growth performance, liver-to-total body mass proportion, and organ-to-total body mass proportion of largemouth bass in the LP-Ly and LL-Ly groups compared to the Control group (P > 0.05). The LP-Ly group exhibited significantly higher condition factor and CP content in whole fish compared to the Control group (P < 0.05). The LP-Ly and LL-Ly groups exhibited significantly lower serum total cholesterol and alanine aminotransferase activity compared to the Control group (P<0.005). Both LL-Ly and LP-Ly groups exhibited significantly elevated protease and lipase activities within their liver and intestinal tissues, as compared to the Control group (P < 0.005). The Control group exhibited a considerably lower level of liver enzyme activities and gene expression of fatty acid synthase, hormone-sensitive lipase, and carnitine palmitoyltransferase 1 in comparison to both the LL-Ly and LP-Ly groups, with a statistically significant difference (P < 0.005). Lysophospholipid supplementation led to an increase in the number of advantageous bacteria, specifically Cetobacterium and Acinetobacter, and a decrease in the number of detrimental bacteria, like Mycoplasma, within the gut's microbial community. In closing, lysophospholipid supplementation in low-protein or low-lipid diets did not hinder largemouth bass growth, but rather activated intestinal digestive enzymes, boosted hepatic lipid processing, stimulated protein accumulation, and modified the composition and diversity of the intestinal microflora.
The substantial increase in fish farming output contributes to a relative lack of fish oil, prompting an urgent need to explore alternative lipid sources. The current study meticulously evaluated the efficacy of poultry oil (PO) as a replacement for fish oil (FO) in tiger puffer fish diets, given their average initial weight of 1228 grams. An 8-week feeding trial was carried out using experimental diets. These diets featured a progressive substitution of fish oil (FO) with plant oil (PO) at levels of 0%, 25%, 50%, 75%, and 100% respectively, identified as FO-C, 25PO, 50PO, 75PO, and 100PO. The flow-through seawater system served as the setting for the feeding trial. Triplicate tanks were each fed a diet. Tiger puffer growth performance remained consistent regardless of the FO-to-PO dietary substitution, as the results demonstrate. A 50-100% PO substitution for FO, even in small increments, yielded a growth boost. Fish fed with PO showed a subtle influence on their body composition, but notably increased the water content in their liver. Dexketoprofen trometamol datasheet Dietary PO consumption typically reduced serum cholesterol and malondialdehyde, however, this was counteracted by an increase in bile acid content. Progressive elevation of dietary PO linearly amplified hepatic mRNA expression of the cholesterol synthesis enzyme, 3-hydroxy-3-methylglutaryl-CoA reductase. Higher dietary PO levels considerably augmented the expression of cholesterol 7-alpha-hydroxylase, a critical regulatory enzyme in bile acid production. Ultimately, poultry oil proves a suitable replacement for fish oil in the diets of tiger puffer. In tiger puffer diets, a complete replacement of fish oil with poultry oil had no detrimental impact on growth or body structure.
To assess the replacement of fishmeal protein with degossypolized cottonseed protein, a 70-day feeding study was performed on large yellow croaker (Larimichthys crocea) with an initial body weight ranging from 130.9 to 50 grams. Dietary formulations, isonitrogenous and isolipidic in nature, were developed using varying proportions of DCP, substituting fishmeal protein with 0%, 20%, 40%, 60%, and 80% amounts, respectively. These were named FM (control), DCP20, DCP40, DCP60, and DCP80. Compared to the control group (19479% and 154% d-1), the DCP20 group (26391% and 185% d-1) demonstrated significantly greater weight gain rate (WGR) and specific growth rate (SGR), with a p-value less than 0.005. Subsequently, fish receiving a diet supplemented with 20% DCP displayed a substantial enhancement in hepatic superoxide dismutase (SOD) activity relative to the control group (P<0.05). A notable decrease in hepatic malondialdehyde (MDA) was observed in the DCP20, DCP40, and DCP80 groups, statistically differing from the control group (P < 0.005). Compared to the control group, the intestinal trypsin activity of the DCP20 group was significantly impaired (P<0.05). Hepatic proinflammatory cytokine gene expression (interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-), and interferon-gamma (IFN-γ)) was markedly greater in the DCP20 and DCP40 groups than in the control group, demonstrating a statistically significant difference (P<0.05). In the target of rapamycin (TOR) pathway, the hepatic target of rapamycin (tor) and ribosomal protein (s6) transcripts increased substantially, whereas hepatic eukaryotic translation initiation factor 4E binding protein 1 (4e-bp1) gene transcripts decreased significantly in the DCP group compared to the control group (P < 0.005). Based on the results from applying a broken-line regression model to WGR and SGR data against dietary DCP replacement levels, the recommended optimal replacement levels for large yellow croaker are 812% and 937%, respectively. The study's findings revealed that the replacement of FM protein with 20% DCP led to a promotion of digestive enzyme activities, antioxidant capacity, immune response, and the TOR pathway, ultimately contributing to better growth performance in juvenile large yellow croaker.
Macroalgae are emerging as a possible component for aquafeeds, demonstrating several beneficial physiological impacts. Worldwide, freshwater Grass carp (Ctenopharyngodon idella) has been a major fish species produced in recent years. To evaluate the potential use of macroalgal wrack in feeding C. idella juveniles, experimental groups were fed a commercial extruded diet (CD), or a diet enriched with 7% of a wind-dried (1mm) macroalgal powder. This powder derived from either a multi-species (CD+MU7) or a single-species (CD+MO7) wrack harvested from the Gran Canaria (Spain) coast. Following a 100-day feeding period, fish survival rates, weights, and body indices were assessed, and samples of muscle, liver, and digestive tracts were obtained. To ascertain the total antioxidant capacity of macroalgal wracks, the antioxidant defense response and digestive enzyme activity of fish were investigated. Finally, the study delved into the composition of muscle tissue, exploring lipid classes and fatty acid profiles in detail. Our study indicates that the addition of macroalgal wracks to the diet of C. idella has no adverse impact on its growth, proximate and lipid composition, antioxidant capacity, or digestive capabilities. In reality, macroalgal wrack from both types caused a reduction in general fat storage, and the multiple species wrack elevated liver catalase function.
Given the observed elevation of liver cholesterol from a high-fat diet (HFD) and the alleviation of lipid deposition through enhanced cholesterol-bile acid flux, we speculated that the promotion of cholesterol-bile acid flux is an adaptive metabolic response employed by fish when consuming an HFD. The current study focused on the characteristics of cholesterol and fatty acid metabolism in Nile tilapia (Oreochromis niloticus) exposed to a high-fat diet (13% lipid) over four and eight weeks. Randomly distributed into four treatment groups were visually healthy Nile tilapia fingerlings (averaging 350.005 grams). These groups comprised a 4-week control diet, a 4-week high-fat diet (HFD), an 8-week control diet, and an 8-week high-fat diet (HFD). High-fat diet (HFD) intake, both short-term and long-term, was studied in fish for its impact on liver lipid deposition, health status, cholesterol/bile acid levels, and fatty acid metabolism. Dexketoprofen trometamol datasheet Serum alanine transaminase (ALT) and aspartate transaminase (AST) enzyme activities, as well as liver malondialdehyde (MDA) content, remained unchanged following four weeks of a high-fat diet (HFD). Fish receiving an 8-week high-fat diet (HFD) showed a significant rise in the activities of serum ALT and AST enzymes, and an increase in liver MDA. A notable feature in the livers of fish fed a 4-week high-fat diet (HFD) was the significant accumulation of total cholesterol, mainly cholesterol esters (CE). This was accompanied by a slight increase in free fatty acids (FFAs), but triglycerides (TG) remained relatively stable. The liver of fish fed a four-week high-fat diet (HFD) underwent molecular scrutiny, revealing a clear accumulation of cholesterol esters (CE) and total bile acids (TBAs), which was largely attributed to the intensification of cholesterol synthesis, esterification, and bile acid production. Dexketoprofen trometamol datasheet Following a 4-week high-fat diet (HFD), fish displayed increased protein expressions of acyl-CoA oxidase 1/2 (Acox1 and Acox2), vital rate-limiting enzymes for peroxisomal fatty acid oxidation (FAO) and instrumental in the transformation of cholesterol into bile acids. A notable 17-fold increase in free fatty acids (FFAs) was observed in fish subjected to an 8-week high-fat diet (HFD). This was accompanied by the unchanged levels of triacylglycerols (TBAs) in the fish liver, and a suppression of Acox2 protein expression. Concurrently, the cholesterol/bile acid synthesis pathways were also impaired. Thus, the vigorous cholesterol-bile acid exchange functions as an adaptive metabolic process in Nile tilapia when given a short-term high-fat diet, conceivably by stimulating peroxisomal fatty acid oxidation.